Clutch wear signal



Aug. 19, 1947. o. J. BLOMBERG 2,425,935

CLUTCH WEAR SIGNAL Filed Jan. 22, 1944 2 Sheets-Sheet 1 2 Sheets-Sheet 2 o; J. BLOM BERG CLUTCH WEAR SIGNAL Filed Jan. 22, 1-944 Aug. 19, 1947.

I A 7A CL U TCH SIGNAL SW1 TCH SIGNAL STAPZ'ER/ SW1 TCH IGNITION 5 WITCH Patented Aug. 19, 1947 CLUTCH WEAR SIGNAL @ttc .l. Elomberg,

Chicago, Ill., assignor, by

mesne assignments, of one-half to Katharine Q. Barnett, Glencoe, Iii.

Application January 22, 1944, Serial No. 519,290 6 Claims. (01. 192-110) This invention relates to an improved device for automatically sounding an alarm or actuatany other signal whenever certain parts subject to e been worn down to a point ere ires attention, replacement or readjustment.

More specifically, my invention is designed for use in motor vehicles in connection with the clutch mechanism whereby whenever the clutch plates become unduly worn or out of adjustment the driver will be automatically notified of that fact.

In its ordinary application my invention comprises a circuit closer which is normally held open by the position of the clutch plates when in normal adjustment but the clutch plates wear, the resulting change in clearance of the clutch opening and closing mechanism, such as the ordinary clutch pedal, will cause the electric circuit to be closed and the danger signal to be actuated.

In the drawings, I have assumed a conventional clutch involving usual clutch members, such as the driven and driving 1.113 565, the usual strong clutch spring which holds these plates in operative engagement with each other, the usual spring actuated clutch opening or throw-out lever and a circuit closer mounted on the floor board of the car, and having a normally open circuit closing button engaging th clutch throw-out lever and arran ed to be moved to close an electric circuit as the wear of the clutch plate allows the shaft of the clutch throw-out lever to move more closely to the underside of the floor boar One side of the circuit closer is grounded, as, for example, through the clutch throw-out lever. The other side of the circuit closer is electrically connected with the horn, a buzzer signal, light or other suitable signal, with suitable connections to the battery so that when the circuit is closed by the sufiicient automatic return movement of the clutch throw-out lever the signal is actuated.

With many motor vehicles the parts are so yieldingly mounted that as the clutch plate first wears to a point permitting closure of the circuit, the closure will be intermittent and the signal will be correspondingly intermittent, but if the parts are not then adjusted, the wear of the clutch plate will progress to a point where the closure and signal will be constant.

In the accompanying drawings,

Fig. 1 shows a clutch actuated pedal, in connection with my circuit closing device mounted on the floor board.

Fig. 2 is a cross-section through the circuit closing device in engagement with the shaft of 2 the clutch pedal looking in the direction of the arrow 3 in Fig. 1 with the circuit closed.

Fig. 3 is a, cross-section through the circuit closing device at right angles to Fig. 2, showing the electrical conductor connected with the insulated plate of the circuit closer and showing the closing button indicated in successive positions.

Fig. 4 is similar to Fig. 3 with the parts shown partially nclosed and partially in section,

Fig. 5 is a typical diagram of the wiring and connected parts.

In the drawings, 1 represents the floor board of an automobile, 2 the clutch pedal, 3 the shaft of the clutch pedal, 4 the return spring of the clutch pedal, 5 a portion of typical clutch shifting mechanism, 6 a portion of the clutch housing. 7 is a housing, within which is mounted a contact plate 8, suitably connected with a conductor, such as M, to complete the circuit. The contact plate is insulated by suitable insulating material 9. it is a button which is shown as adjustably mounted on an adjustment screw I! and normally held out of contact with the plate 8 by a spring I 2. The lower end of the spring 52 is conveniently contained in a cap is. The button is may be conveniently grounded, for example, as shown in Fig. 2, through the screw l l and the clutch lever shaft '3.

In Fig. 3, the contact plate 8 is connected in the electric circuit through the conductor It.

By this arrangement it will also be seen that the spring actuated cap 53 and the parts con nected therewith will serve as a resilient stop for the shaft 3 of the clutch pedal. While the clutch pedal return spring 5 is strong enough to return the clutch pedal to normal position, it-is not sufficiently strong to overcome the resilience of the spring E2 on the closure button and while the spring 52 offers sufficient resistance to the action of the clutch lever return spring 4, so as to hold this circuit open under normal conditions and so as to act as a resilient stop for the shaft of the clutch pedal, on the other hand, the spring 12 will yield to the pressure of the conventional clutch plate actuating springs, not shown, so that when the clutch plate wears, the force of the clutch actuating springs will overcome the resilience of the circuit closer spring l2 and permit the button I0 to be moved into contact with the plate 8 and thus close the circuit and sound the alarm signal. With the clutch in normal adjustment the engagement of certain of the clutch parts will stop the return movement of the clutch throw-out pedal shaft short circuit closing position.

With this explanation, it will be seen that when the clutch plates are in normal adjustment, the pressure of the clutch plate springs will bring "he clutch plates into operative engagement while the clutch shaft 3 has such clearance below the floor board. i that the alarm signal. will not be closed. As the clutch plates wear, the preset of the clutch engaging springs exerted through the clutch lever will gradually close the clearance between the clutch shaft 3 and the floor board l until ultimately the button Hl come in contact with the plate 8, closing the circuit and actuating the alarm signal.

Figure 5 is a typical wiring diagram. With the parts arranged and wired as there shown, it is apparent that when the ignition switch is open, my alarm device will be inoperative, but as soon as the ignition switch is closed my safety device becomes immediately operative and will sound the alarm whenever the clutch mechanism requires adjustment or requires the replacement or worn clutch plates.

Obviously my invention be adapted to any form of clutch operating mechanism by so mount-- ing the circuit closing mechanism as to automatically close the alarm circuit whenever the wear or maladjustment of the cl itch mechanism pormits such an increased. movement of clutch ac-- tuating mechanism as to close the alarm circuit.

I claim:

1. In combination with clutch mechanism 0 automobile, of a circuit closer mount circuit closer sp mg whereby c c i c is closed whenever the clutch requires adjustment.

2. In a device of the class de oed, the c bination with clutch plates, resi ent means ranged to normally hold plates in operative engagement with each other, a lever to disenga e said plates and be returned towards normal position by said resilient means, a spring tending to move said lever in a switch closing direction, a switch adapted to be closed by said lever, a spring holding said switch in open position, said spring having greater strength than the lever sprin but or"; less strength that-i the resilient plate holding means whereby the switch is normally held open but will be moved to closed. position by the further movement of said lever in a switch closing direction by said resilient means due to wear or maladjustment of said clutch plates.

3. In a device of the class described, the combination with clutch plates, resilient means ar direction due to wear or maladjustment of said clutch plates, said switch comprising a resilient circuit closing member mounted on a stationary s' ort serving as a resilient stop for said 5 when said lever is actuated by said spring.

l. The combination with a clutch of a clutch pedal shait clutch spring that will move said shit oppositely from disengaging movement as he clutch wears, a clutch pedal return spring rmally holding said shaft in a retracted position and a circuit closer adapted to be closed by the clutch spring actuated movement of said chart beyond its normal position.

In combination a clutch comprising pressure plates, spring means for holding said plates in operative relation to each other, a throw-out lever arranged to disengage said plates from such opve relation and be returned towards normal pc. tion by said spring means, resilient means for normally returning said lever to a position of r st, a circuit cioser actuated by the return movement or said lever by said spring means beyond nal position, and adjustment means on said circuit closer whereby circuit closer is normally actuated to closing position only when the clutch requires adjustment.

6. In a device or the character described, the --....nation with an actuating lever of a stationary support, a spring for holding the lever in a position of rest, a circuit closer mounted on said support, a spring normally holding said circuit closer in open position, said circuit closer enga 5 said lever and serving as a resilient stop for said lever, clutch means adapted to be disengaged by said lever, spring means normally holding said clutch in engaged position all so arranged that wear of the parts arranged to be actuated by said lover and normally acting as a positive stop to limit the spring actuated movement of the r, will hermit the clutch sp ing means to cause lever to compress the resilient member of aid stop sufliciently to permit movement of said circuit closer to closed position.

OTTO J. BLOMBERG.

DI FERENCES CITED erences are of record in the his patent:

UNITED STATES PATENTS Name Date Schmidt et a1 July 6, 1943 Wesolek June 17, 1919 Morri n June 22, 1926 Keppel Sept, 7, 1930 Norviel Aug. 23, 1932 

